1In a medium bowl, combine cream cheese, mayonnaise, shredded cheese and garlic salt. Beat until smooth.
2Preheat a large skillet over medium heat. Spread cheese mixture on 4 slices of bread, then top with the other 4 bread slices. Lightly butter both sides of each sandwich. Place sandwiches in skillet, and grill until golden brown on both sides, about 4 minutes per side.